In order to measure or monitor whether a refrigeration system is operating correctly or to diagnose a problem, it is necessary to measure the pressure of the refrigerant in either of the high and low pressure sides of the system or both. Basically, the conventional units which are used for this purpose are manifolds with flexible tubes which are connected to pressure nipples provided on the refrigeration system. The manifolds are provided with analog gauges. One gauge is connected to the high pressure side and one gauge is connected to the low pressure side of the refrigeration system. The gauges measure pressure but corresponding boiling point or saturation temperature values are given for the refrigerant at the different pressure values. The boiling point or saturation temperature is the temperature at which a phase change between the vapour and liquid phases occurs for the refrigerant at a particular pressure.
It is an object of the present invention to provide a pressure measuring system which will facilitate the operations of carrying out pressure measurements and obtaining corresponding boiling point temperature values for different refrigerants.